Aust backs Assad investigation: Bishop

The Turnbull government is backing an investigation into whether the Syrian government is responsible for a chemical attack which killed more than 70 people, many of them children.

Foreign Minister Julie Bishop said Australia supports a United Nations probe into what she described as an illegal and horrific event.

"We certainly call for a full investigation and if the Assad regime is found to be responsible, as many have claimed, then those responsible must be brought to account," she told ABC radio on Thursday.